One feature of a flower that is specifically adapted to attract hummingbird moths, which are known for their rapid hovering flight and preference for certain flower types, is a tubular shape. This shape allows the moths to easily access the nectar while simultaneously promoting effective pollination as they brush against the flower's reproductive structures.
Regarding the second part of your question about whether flowers would be more reproductive, it's important to note that flowers with traits specifically evolved to attract particular pollinators, like hummingbird moths, often enhance their reproductive success. By attracting these efficient pollinators, flowers can increase the likelihood of cross-pollination, leading to greater genetic diversity and successful seed production. Overall, adaptations for attracting specific pollinators can play a significant role in the reproductive success of flowering plants.